Instantaneous fuel burner and method of burning fuel



May 26, 1925. 1,539,111

C- A. FRENCH ET AL INSTANTANEOUS FUEL BURNER AND METHOD OF BURNING FUEL Filed JUIIQ 8, 1922 1 2 Sheets-Sheet l Tn'zzeniorp. RP a hazze fll 'razwk MLccurmE G o i May 26,1925.

C. A. FRENCH ET AL INSTANTANEOUS FUEL BURNER AND METHOD OF BURNING FUEL m W3 W WW y Patented May 26,1925.

' NIT-ED S TE ATENT ounce,

CHARLES A. FRENCH AND LAURANCE E/GOIT, OF CHICAGO, ILLINOIS, ASSIGNORS TO INTERNATIONAL HARVESTER COMPANY, OF'CHICAGO, ILLINOIS, A CORPORA- TION or NEW JERSEY.

msmnzmnnous FUEL BURNER AND .mnrnon or BURNING FUEL.

' Application filed June a, 1922. Serial No. 566,886.

' To dlZwkom it concern:

Be it known that we, CHARLES A. FRENCH and LAURANon E. Gorr, citizens, of the United States, and residents of Chicago, in

the county of Cook and State of Illinois,

have invented certain new and useful Improvements in Instantaneous Fuel Burners and Methods of Burning Fuel, of which the following is 10 particularly to burners using kerosene, disv tillate and the heavier oils for fuel and to a method of burning fuel.

The ordinary burner using fuel oil (kerosene or heavier) must beheated from an external source-t0 a temperature sufficiently high to vaporize the fuel before it can be started. This preheating requires from two to ten minutes before the burner is ready for normal operation. In automotive steam power plantsthis delay inv starting the burner is entirely too great and has been one very.material factor in limiting the adoption of steam propelled motor vehicles. h

The principal object of our invention therefore is to provide a burner utilizing relatively heavy oil for fuel that may be started instantly (as'by a sparkplug) and will burn from the start with a clean, blue flame, there being no carbon deposits or soot formed at any sta e of the operation of the burner no matter ow long or short time it may continue in operation.

riefly stated, our, 1nvention involves a 1 burner and method of burning fuel in which the fuel is finely divided by blowing itover a sharp atomizing edge with an air blast which supplies only enough air to form a -combustible' mixture with the very small amount of the fuel that is vaporizable at low temperatures. 'This mixture is then ignited and as it burns in the presence of the heayler particles of fuel, more .fuel is vaporized by-the heat therefrom and proportionately more air added to form ,a conrbustible mixture therewith. This stage or' operation continuesv progressively, that is, more'fuel vaporized and more air added soas to keep a blue burning until that point is reached at, where the fuel is which "the combustion may be accelerated by addition of suflicient air tocompletely burn all the fuel with" a blue flame.

. Reference will now be had to the drawings, in each of the figures of which we have shown a burner embodying the principles of our invention and adapted to carryout our improved process of combustion.

In Figures 1 and 2 we supply the fuel directly to the atomizing edge by an impeller,

while in Figure Zftlle' fuel is distributed to the atomizing edge by an air blast.

In Figure 1, ourimproved burner has a casing 5 closed at its upper end by a hood 6 having an air inlet 7 controlled by a throt tle valve 8. A vertical shaft 9journaled in the hood 6 is drivenby a belt pulley 10v secured -toits upperend and carries an air propelling fan 11 which draws in air through the inlet? and a central outlet 12 1n the hooddelivering' it radially from the fan "blades. into the burner casing. The i shaft extends downward into the casing below-the fan and at its lower end supports a bowl 13 having a plurality (preferably 4) of hollow radial arms 14 through which fuel supplied to the bowl from a. pipe 15 is; distributed. An annular grating 16 has a pluralrt'yv of rows of graduated perforations 17 of increasing diameter from top to bottom and extends upwardly into the'casing being secured thereto by a flange 18. An annulus 19 is secu-redto the top of the grating and has a sharp circular edge 20 for ,atomiz-in the fuel. An inner grating 21 .is secure within the outer grating 16 by means of bolts 22 and has similar graduated perforations 23. At its top side the grating 21 has an annular lip 24 extending into close proximity to the edge 20 whereby a narrow annular opening 25 is provided for the passage of the fuel and a restricted amount'of air.

An annular deflector 26 directs the passage of air from the fan 11. toward the center so that air is "supplied to the central grating spark plug 27 orother form of igniter extends through the easing into the combustion ,zone 28 between the two gratings a '21. as well as to the ,outer grating 16; A

short distance below the atomi'zing edge ignited. v

In operation, the pulley 1'0 drives the fan 11 to draw in air through the inlet 7 towhich air maybe supplied .at atmospheric pressure or under slight pressure from a blower. The air is delivered by the fan under slight pressure to the casing 5 where it divides, part passing to. the outside of the grating 16 and part to the inside of the grating 21 from where it passes through the perforations l7 and 23 into the combustion zone. Fuel is suppliedito the bowl 13 from the fuel pipe 15 and is distributed by centrifugal force through the arms 14 and small perforations 29 in a finely divided liquid state to the surface of the ring 19 near the sharp edge 20 from which it is blown in a finely atomized condition by the blast of air flowing through the narrow opening 25. The velocity and pressure of the air flowing over the atomizing edge are considerably increased by the arms Hwhich operate as impeller blades on the air.

As the fuel and air leave the sharp edge 20, a small amount of the fuel will be vaporized and mix with .the air to form a combustible mixture which is ignited by the spark plug 27. This mixture burns as it passes, downward in, the combustion space between, the grates, the great excess of fuel retarding the combustion so that not enough 1 heat is generated to decompose the unburned particles but sufficient is developed to partly vaporize the particles and allow the vapor to diffuse evenly and, as the fuel particles and vapor pass the openings 17,:a

the combustion -at a low rate or below the rate of complete decomposition of ,the fuel. This combustion is relatively cold, and, as it progresses, the fuel vapors are progressively cracked into smaller and smaller par ticles, the tendency of which to decompose is less noticeable the smaller they become. Eventually a point is reached at which the hydro-carbon particles are cracked .down so that the combustion may be accelerated to the greatest possible extent without. producing decomposition of the fuel. The result is that our burner burns with a clean, short, blue flame as soon as it is started and there is absolutely ,no deposit of carbon or formation of soot. I

The burner of Figure 2 operates similarly to that of Figure 1 but differs slightly in de tailslof construction. Air is supplied under pressure to the inlet and drives the turbine 31 mounted on the shaft 32 which carries a bowl 33 at its lower end to receive fuel from a supply pipe 34;. The bowl has a plurality of hollow radial arms or pipes 35 which distribute the fuel to the atomizing edge '36 in the same manner as in Figure 1. The mixture is fired by an igniter 37 and additional air is supplied through the graduated perforations 38 and 39 in the inner and outer gratings -l0 and 41 respectively.

In Figure 3 the burner casing comprises upper and lower sections 43 and H secured together by bolts 45. The upper section carries a shaft 46 and has an inlet 47 through which air is supplied to the impeller or fan 48, the fan also serving to distribute fuel supplied through a pipe 49. The fan is driven by a pulley 50 mounted on the shaft 46. The air and.fuel are thrown outward by the impeller against the curvedinner wall of the casing, the fuel and some of the air following the wall'down to the atomizing edge 51 from which the fuel is blown in, finely atomized condition into the combustion space 52 where it is fired by an igniter 53 and burns slowly. Additional air is supplied through.perforations 54 in the grating 55 to progressively increase the combustion until the fuel is vaporized and cracked to such an extent that when it issues from the annular opening 56 into the path of the air coming down through the grating nozzle 57 at high velocity it will burn with a clean, blue flame. The. velocity of the air through the nozzle 57 is quite high and the combustion in the chamber 52is not necessarily carried as far as it is in the combustion chambers-of Figures 1 and 2 before sufficient air is addedfor complete'combustion. \Ve have found'if the air is supplied to the partly burned and cracked fuel at high velocity, that this velocitymay be substi- 23, only enough air is supplied to continue Ntuted for a portion of the precombustion,

that is, the precombustion may be stopped}- at an earlier stage and the final stagelicompleted without the formation of soot or can bon deposits.

In a burner constructed according to-our invention with the atomizing edge having-a: circumference of approximately 24 inches,; the bowl having four fuel distributing arms or vanes, the fan runningat approximately 3,000 R. P. 1 and the burner consuming.

about 35 pounds of fuel per hour, each in-' cremental length of the edge will receivefuel 200 times per second, the entire cir-' cumference, receiving .0096 pounds of fuel per second which results in a. ver atomization. The fuel is delivered about A;' inch above the-edge and its fine distribublowing it over a sharp edge with a supply of air insuificientfor complete combustion,

burning a portion of the fuel in the insufficient air supply to vaporize the fuel and crack it into simpler hydrocarbons, adding more air and burning more fuel to increase the vaporization and cracking, ahd contin- -uing the combustion with the addition of progressively increasing quantities of air" I and progressively increasing cracking of the fuel until that point is reached at which air sutticient for complete combustion may be added and the combustioncompleted with out decomposition of the fuel.

2. That method of burningfuel which comprises mixing the fuel in a relatively cool state-with an amount of relatively cool air insufficient for complete combustion,

1 burninga portion of the fuel in the insufi'ict ent air supply at a temperature below that.

of decomposition of the fuel, progressively adding quantities of air suflic ient to continue the combustion at a temperature sufficient to vaporize and crack the fuel but insufli'cient to decompose the fuel and finally adding iuflicient air for complete combustion of the uel.

3. In a burner, the combination of a circular grating having an annular atomizing edge, means providing a restricted passage adjacent the edge, means for supplying fuel to the edge, means for supplying a blast of air through the restricted passage and over the edge whereby the fuel is atomized and mixed with the .air, and means for igniting the mixture.

4. In a burner, the combination of a grating having an atomizing edge, means providing a restricted pasa-ge'adjacentthe edge,

. means for supplying fuel to the edge, means for'supplying a blast of air through the irestricted passage and over the edge whereb the fuel is atomized and mixed with the air, means for igniting the mixture, and means for supplyin additional air to the mixture after ithas been ignited. j

' P5. In a burner, the combination of a grating having an atomizing edge, means providing a restricted passage adi acent the edge,

means for supplying fuel to the edge, means for supplying a blast ofair through the restricted' passage and over'the ed e whereby the fuel isatomized and mixed with the air, means. for igniting the L mixture, and means for successively adding further quantities of air to the burning mixture.

' I In burner, :the combination of a grat- 5 mg having an atomized edge, means providing-a restricted passage adjacent the edge, means for supplylng fuel to the edge, means for supplying a blast of air through the ly increasing amo restricted passage and over the edge .Wherebythe fuel is atomized and mixed with the air, means for igniting the mixture, and means for successively adding progressive mixture.

7.- In a burner, the combination of an anmts of air to the burningnular grating having perforated sides and a sharp annular edge at one end, an annular lip providing with the sharp edge a constricted annular passage, means for sup-. plying fuel to the edge, means for forcing air through the annular. passage to atomize the fuel, means for igniting the atomized fuel and air after it has left the edge, and means for supplyingadditional air to the burning mixture throughthe perforations in the grating. v Y

8. In a burner, the combination of two concentric perforated gratings providing a combustion zone therebetween, an annular sharpedge and lip on the respective gratings providing a restricted annular pas sage comunicating with the combustion zone, means for creating a blast of air andfuel. over the sharp edge and into the combustion zone, and meansfor supplying additional air thereto throug the perforations in the gratings.

9. In a burner, the combination of a casing, means providing an annular combustion chamber therein, centrifugal means above the chamber for supplying a mixture of air and. fuel thereto, means extending through the casing and into the chamber for chamber therein, centrifugal means at one end of the chamber: for supplying a mixture of air and fuel to one end of the combustion chamber, means extending through the y casing for igniting the mixture in the com- -bustion chamberhear said'end,-and means for supplying a successively increasing amount of air to the burning mixture through the walls of the combustion chamber Withthe largest amount of air coming inat the otherfend offthe chamber.

11. In a burner, the combination of a casing, a shaft rotatably mounted therein. a

grating in the casing having an annular sha 'rortdtitble with the shaft for distributing fuel to the sharpedge, means for directing a. blast of airover the sharp edge to atomize "the fuel, means for igniting the mixture of air and fuelas it leaves the sharp edge, and means for supplyingadditional air to the burning mixture. j. r

12. In a burner, the combination of a casing, a shaft rotatablys mounted therein, a grating in the casing having an, annular sharp edge concentric with said shaft, a bowl rotatable withthe shaft and having a plurality ofhollow arms terminating adjacent the sharp edge and adapted to deliver fuel thereto, means for supplying fuel to the edge concentric with the shaft, means bowl, and an air impeller rotatable with/the shaft for directing a blast of air over the sharpedge and through perforations in the grating.

13. In a burner, the combination of a casing, a shaft rotatably mounted therein, two concentric perforated gratings providing an annular combustion chamber, an annular sharp edge and lip on the respective gratings coaxial with the shaft, a bowl rotatable with the shaft and having a plurality of hollow arms terminating adjacent the sharp edge, means for supplyin fuel to the bowl, means rotatable with the s aft for directing a blast for supplying and directing a. combustible mixture to said chamber, means for igniting the mixture in the chamber, and means for supplying additional air to the chamber through perforations in the gratings.

15. In a burner, thefcombination of a casing, a pair of concentric perforated gratings mounted in the casing and spaced apart to form a combustion chamber between them, means for supplying a combustible mixture to the chamber, and means for igniting the mixture in the chamber, the perforations ini the gratings being so arranged and formed that additional air may be progressively added to the burning mixture in successively increasing quantities.

16. In a burner, the combination of a. casing, a pair of concentric gratings mounted in the casing and arranged to form a combustion chamber between them gradually increasing in size from one end to the other, meansfor supplying a combustible mixture to the chamber at its smaller end, means for igniting the mixture, and means for adding 17. In a burner, the combination of a casing,,a pair of gratings forminm a combustion chamber between them and carried by said casing, centrifugal means. for supplying. fuel to said chamber including a phrrality of hollow arm's terminating adjacent the chamber, means for supplying air to the chamber, and means for igniting the mixture 1n the chamber.

additional air through the walls of the V gratings t0 the chamber at its larger end.

18. In a burner, the combination of a casing, a pair of spaced concentijc gratings mounted in the casing,-a vertical shaft rotatably mounted in the casing, a bowl rotatable with' the shaft and adapted to "deliver fuel between the gratings, and an impeller rotatable with the shaft and positioned above the bowl for directing a blast of air downwardly between the gratings.

In testimony whereof we affix our signatures. i

- -'CHARLES A. FRENCH.

- LAURANCE E. GOI 'II. 

